R32 T38 T45 T51 3660mm MF Drill Rod Specification
The 3660mm MF Drill Rod (12 feet in length) is a top hammer extension drill rod specifically designed for deep-hole drilling and high-precision rock drilling operations. Featuring a unique male-female (MF) integrated thread design, this rod offers superior structural rigidity, faster coupling/uncoupling efficiency, and extended service life compared to traditional “male-male” rods used with separate couplings.
As a core component of the drill string system, the 3660mm length is an internationally standard dimension that balances the reach required for deep-hole operations with the practicality of on-site handling.
Key Technical Specifications
| Parameter | Specification |
|---|---|
| Product Name | MF Drill Rod / Male-Female Connection Rod / Speed Rod |
| Overall Length | 3660 mm (12 feet / 12FT) |
| Diameter Options | Typically 32mm – 46mm rod body (Common: Hex32, Hex35, Rnd39, Rnd46) |
| Thread Types | R32, R38, T38, T45, T51 (Trapezoidal or rope thread) |
| Treatment Process | Fully Carburized or Induction Hardened (thread ends) |
Key Advantages & Design Highlights
1. Integrated Connection Design – Enhanced Rigidity & Accuracy
Traditional drill rods require a separate coupling sleeve to connect rod sections. The MF drill rod integrates the female thread directly into one end of the rod body. This design eliminates the microscopic gaps between the sleeve and the rod, creating a tighter connection:
- Straighter Holes: Reduced connection clearance minimizes drill string deviation in deep holes, significantly improving borehole straightness.
- Efficient Energy Transfer: Shock wave energy loss through the integrated connection surface is reduced. Field data shows penetration rate improvements of at least 10%.
2. Operational Convenience – Reduced Auxiliary Time
In confined underground environments, loose small components (coupling sleeves) are easily lost and difficult to manage.
- Quick Make/Break: The MF design allows rod connection and disconnection in a single operation, significantly faster than traditional “rod + coupling sleeve” systems.
- Eliminates Lost Couplings: No risk of a coupling sleeve becoming stuck down the hole, reducing the potential for fishing jobs.
3. Superior Metallurgical & Heat Treatment
The 3660mm MF drill rod must withstand high impact energy and rotational torque, requiring high-quality materials:
- Alloy Steel Material: Manufactured from 23CrNi3Mo or equivalent SANBAR 64 grade alloy steel pipe, offering excellent fatigue strength.
- Hardening Processes:
- Full Carburization: Provides a hard, wear-resistant rod surface, ideal for abrasive rock formations to extend overall service life.
- Thread Hardening: High-frequency induction hardening on the thread ends ensures the most vulnerable areas withstand repeated make-and-break cycles.
| Feature | Traditional Rod + Coupling | MF Male-Female Rod |
|---|---|---|
| Connection Rigidity | Moderate (with clearance) | High (Rigid connection, minimal deviation) |
| Assembly Difficulty | Requires separate coupling handling | Fast, integrated design |
| Application | Shallow holes, low-cost operations | Deep holes, high precision, high efficiency |
Applications
The 3660mm MF drill rod is widely used in the following conditions:
- Underground Mining: Medium-deep hole drilling, rock bolting, raise boring.
- Tunneling: Probe hole drilling, pipe roofing.
- Quarries & Open-Pit Mines: Pre-split holes, curtain grouting, blast hole drilling.
- Hydraulic Engineering: Deep hole drilling for dam foundation reinforcement.
Selection Recommendations
When selecting the 3660mm MF drill rod, match the thread to your rock drill model:
- T38 Thread: Suitable for mainstream medium-light hydraulic jumbos (e.g., Atlas Copco series), typically with Hex35 or Rnd39 rod body. This is the “golden standard” for tunnel drilling.
- T45 Thread: Suitable for higher-power rock drills, typically with Rnd46 rod body. Ideal for deep hole applications requiring higher flushing pressure and torque.
Summary:
Choosing the 3660mm MF Drill Rod means selecting higher drilling accuracy, lower consumable costs (no couplings needed), and faster penetration rates. It represents an ideal solution for achieving high-efficiency, low-cost drilling in modern mechanized rock drilling operations.
